JP2019089098A - Flux, resin flux cored solder, and flux coat pellet - Google Patents

Abstract

To provide a flux, a resin flux cored solder, and a flux coat pellet which can wash with water.SOLUTION: A resin flux cored solder 10 is structured of a linear solder 20, and a flux 30 filled in an approximate center part (an axial center) of a cross section of the solder 20. The flux 30 contains salt-forming amine, and salt-forming organic acid. The salt-forming organic acid is 10-645 pts.mass to 100 pts.mass of the salt-forming amine. The salt-forming organic acid includes at least one organic acid selected from a group of malonic acid, succinic acid, glutaric acid, tartaric acid, malic acid, diglycolic acid, and citric acid.SELECTED DRAWING: Figure 1

Description

  The present invention relates to flux, core solder and flux coated pellets.

  In general, solder bumps are widely used when mounting electronic components on printed circuit boards. The core solder is composed of a linear solder and a flux filled in the approximate center of the cross section of the solder. For example, rosin, modified rosins, and synthetic resins are used as the material of the flux.

  For example, in Patent Document 1, in the case of a soldered yarn solder having a flux in the center of the concentric circle and an alloy layer provided on the outer periphery of the flux, the alloy powder is added to the flux provided in the center of the concentric circle. Is described.

Unexamined-Japanese-Patent No. 2010-046687

  However, in the conventional core solder and the like described in Patent Document 1, the flux contains rosin and modified rosins. Therefore, when it is necessary to wash the flux residue, since the flux residue is made of highly lipophilic rosin or the like, there is a problem that it is difficult to wash the flux residue if water is used as a detergent.

  Then, this invention is made in view of the said subject, and it aims at providing the flux which can be water-washed, a core solder, and a flux coat pellet.

  The present applicant forms a salt using an organic acid known as an activator of a flux instead of rosin and rosin, and forms a salt, and the flux composition is designed using this salt as a base agent of the flux. Was found to be removed by water washing. The present invention is as follows. In addition, since rosin can not be included in the flux to perform water cleaning, it should not be originally called a core solder, but its shape and method of use are the same as conventional cored solder, for convenience. The present invention also refers to solder core solder.

(1) The flux according to the present invention contains an amine for salt formation and an organic acid for salt formation, and the amount of the organic acid is 10 parts by mass or more and 645 parts by mass or less with respect to 100 parts by mass of the amine. And rosin-free.

(2) The flux according to the present invention is characterized in that the amine contains at least one or more of polyoxyalkylene ethylenediamine and 2,2 '-(cyclohexylimino) bisethanol.

(3) The flux according to the present invention is characterized in that the organic acid comprises at least one or more of malonic acid, succinic acid, glutaric acid, tartaric acid, malic acid, diglycolic acid and citric acid.

(4) In the flux according to the present invention, when the flux containing a salt formed by the amine for salt formation and the organic acid for salt formation is 100% by mass, the organic acid not for salt formation is 0 It is characterized in that it is contained by mass% or more and 10 mass% or less.

(5) The flux according to the present invention contains 0 mass% of amine not for salt formation, assuming that the flux containing a salt formed of the amine for salt formation and the organic acid for salt formation is 100% by mass. % Or more and 10 mass% or less.

(6) The flux according to the present invention contains 0% by mass or more of an amine halogen salt, assuming that the flux containing a salt formed by the amine for salt formation and the organic acid for salt formation is 100% by mass. It is characterized in that it contains at most mass%.

(7) The flux according to the present invention contains 0% by mass or more of a surfactant when the flux containing a salt formed by the amine for salt formation and the organic acid for salt formation is 100% by mass. It is characterized in that it contains at most mass%.

(8) The flux according to the present invention is characterized in that the flux is solid at 25 ° C. or a liquid having a rotational viscosity of 3,500 Pa · s or more at 6 Hz at 25 ° C.

(9) The core solder according to the present invention is characterized by including linear solder and the flux according to any one of the above (1) to (8) filled in the solder. I assume.

(10) The flux coated pellet according to the present invention is characterized in that the solder pellet is coated with the flux described in any one of the above (1) to (8).

  According to the present invention, since flux can be formed without using rosin, modified rosin and the like, flux residue can be removed by water washing.

A is a top view which shows the example of a structure of the core solder concerning one embodiment of this invention, B is the sectional view. A is a perspective view which shows the example of a structure of the pellet based on one embodiment of this invention, B is the sectional view.

  The present invention will now be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown.

  FIG. 1A is a front view showing an example of the configuration of a core solder 10 according to an embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along the line A-A.

  As shown in FIGS. 1A and 1B, the core solder 10 according to the present invention comprises a linear solder 20 and a flux 30 filled substantially in the center (axial center) of the cross section of the solder 20. It is configured.

  The solder 20 may be, for example, a Sn—Ag based alloy, a Sn—Cu based alloy, a Sn—Ag—Cu based alloy, a Sn—In based alloy, a Sn—Bi based alloy, and Ag, Cu, Ni, An alloy to which Co, Ge, Sb, In, Bi, Fe, Cr, Zn or the like is added can also be used. In addition, in the case of lead-containing alloys, Sn-Pb alloy, Sn-Pb-Ag alloy, Sn-Pb-Bi alloy, and alloys of these, Ag, Cu, Ni, Co, Ge, Sb, In, Bi, Fe Alloys to which Cr, Zn, etc. are added can also be used.

  The flux 30 for core solder contains an amine and an organic acid. In this embodiment, a salt is formed by neutralizing an amine with an organic acid, and the formed salt functions as a base agent to be substituted for rosin, modified rosins, and the like. As a result, the flux 30 for the core solder becomes a solid or liquid of high viscosity at room temperature. Here, that the flux 30 is a liquid with high viscosity means that the rotational viscosity of the flux 30 at 6 Hz is at least 3500 Pa · s when the viscosity of the flux 30 is measured using a rheometer at 25 ° C. Say. Hereinafter, the amine that forms the above-described salt is referred to as a salt-forming amine, and the organic acid that forms a salt is referred to as a salt-forming organic acid.

  As the salt-forming amine, for example, at least one amine selected from the group consisting of polyoxyalkylene ethylene diamine and 2,2 '-(cyclohexylimino) bisethanol can be used. Polyoxyalkylene ethylene diamine is represented by the following chemical formula.

  R1 to R4 represent side chains. In polyoxyalkylene ethylenediamine, two polyoxyalkylene groups are bonded to N atoms at both ends of ethylenediamine.

  As polyoxyalkylene ethylene diamine, for example, tetrakis (2-hydroxypropyl) ethylene diamine, polyoxypropylene ethylene diamine, polyoxyethylene polyoxypropylene ethylene diamine can be used.

  As the salt-forming organic acid, for example, at least one organic acid selected from the group consisting of malonic acid, succinic acid, glutaric acid, tartaric acid, malic acid, diglycolic acid and citric acid can be used. The salt-forming organic acid functions as an activator for improving the wettability of the solder 20 by heating at the time of soldering.

  The mass ratio of the salt-forming amine to the salt-forming organic acid in the flux 30 is 10 parts by mass to 645 parts by mass of the salt-forming organic acid with respect to 100 parts by mass of the salt-forming amine. By setting the salt-forming organic acid to 10 parts by mass or more and 645 parts by mass or less, the salt formed with the salt-forming amine can be made into a solid or highly viscous liquid.

  Further, the flux 30 for core solder is an organic acid not for salt formation, assuming that the entire flux 30 containing a salt formed by the salt forming amine and the salt forming organic acid is 100% by mass. It can also be configured by adding 0 mass% or more and 10 mass% or less. As an organic acid which is not for salt formation, for example, glycolic acid, propionic acid, 3-hydroxypropionic acid, lactic acid, acrylic acid, glyceric acid, 2,2-bishydroxymethylpropionic acid, 2,2-bishydroxymethylbutane An acid or the like can be used.

  In addition, when the flux 30 containing a salt formed by the salt-forming amine and the salt-forming organic acid is 100% by mass, the flux 30 for the core solder is 0 for the amine not for salt-forming. It can also be constituted by adding at least 10% by mass. Examples of amines not for salt formation include, for example, methanolamine, dimethylethanolamine, N-methylethanolamine, diethanolamine, triethanolamine, terminal amine (polyoxyethylene-polyoxypropylene) copolymer (terminal amine PEG-PPG copolymer) Etc. can be used. Solderability (oxide film removability) can be further improved by adding to the flux 30 an amine which is not for salt formation which functions as an activator.

  Further, the flux 30 for core solder is 0 mass% or more of an amine halogen salt, assuming that the entire flux 30 containing the salt formed by the salt forming amine and the salt forming organic acid is 100 mass%. It can also be constituted by adding 15% by mass or less. By adding an amine halogen salt that functions as an activator to the flux 30, it is possible to further improve the solderability (oxide film removability).

  In addition, the flux 30 for core solder is 0 mass% or more of surfactant, assuming that the entire flux 30 containing a salt formed by the salt forming amine and the salt forming organic acid is 100 mass%. It can also be configured by adding 10% by mass or less. By adding a surfactant to the flux 30, it is possible to improve the water washability.

  Further, the flux 30 for core solder is an organic acid not for salt formation, assuming that the entire flux 30 containing a salt formed by the salt forming amine and the salt forming organic acid is 100% by mass. It can also be comprised by adding 0 mass% or more and 25 mass% or less in total of the amine and amine halogen salt which are not for salt formation. By adding a surfactant to the flux 30, it is possible to improve the water washability.

  As described above, according to the present embodiment, since the flux 30 is formed without using rosin or modified rosins, the flux residue can be reliably removed even when water is used as the cleaning liquid. In addition, since water can be used as the cleaning liquid, it is possible to realize simple and environmentally friendly cleaning of the flux residue. As the application of the solder core 10 according to the present embodiment, for example, the soldered portion of a substrate soldered with a water-soluble paste or the like can also be used at the time of repair work.

  In the embodiment described above, an example in which the flux 30 is applied to the wire cored solder 10 has been described, but the present invention is not limited to this. For example, the flux 30 described above can also be used as a flux for solder pellet coating.

  FIGS. 2A and 2B show an example of the configuration of a flux coated pellet 50 using the flux 30. FIG. As shown in FIGS. 2A and 2B, the flux-coated pellet 50 is composed of a solder pellet main body 40 having a rectangular parallelepiped shape, and a flux 30 covering the upper and lower surfaces thereof. For the solder pellet body 40, the same material as that of the solder 20 described above, for example, a Sn—Ag—Cu-based alloy can be used. For the flux 30, the above-described material, specifically, a material containing an amine and an organic acid can be used. The flux 30 is applied to the upper and lower surfaces of the solder pellet 60 after being heated and melted. The flux 30 is applied not only to the upper surface and the lower surface of the solder pellet body 40 but also to the side surface (peripheral surface) of the solder pellet body 40 so that the entire solder pellet body 40 is covered with the flux 30. Also good. According to the flux-coated pellet 50 of the present embodiment, as described above, since the flux 30 is formed without using rosin or modified rosins, the flux residue can be reliably removed even when water is used as the cleaning liquid. Can.

  The flux was produced by the composition of the Example shown in following Table 1-Table 3, and the comparative example, and the solidifying property in the produced flux and the washability of the flux residue were verified, respectively. The present invention is not limited to the following specific examples.

(1) Evaluation Method of Flux Coagulability The produced flux was stored at room temperature of 25 ° C., and it was determined whether the flux was solid or liquid. When the flux was liquid, the viscosity of the flux was measured using a rheometer. Specifically, the flux was sandwiched between the plates of a rheometer (Thermo Scientific HAKE MARS III), and the viscosity of the flux was measured by rotating the plate at 6 Hz.

The viscosity of the flux was evaluated based on the criteria shown below.
:: When the flux is stored at 25 ° C. When the flux is solid ○: When the flux is stored at 25 ° C. It is a liquid, but when the viscosity measured with a rheometer is 3500 Pa · s or more x: The flux When it is a liquid when stored at 25 ° C and its viscosity measured by a rheometer is less than 3500 Pa · s

(2) Evaluation method of the cleaning property of the flux residue On the copper land of the glass epoxy substrate, the flux-filled core solder of each example and comparative example was heated for 5 seconds using a soldering iron at 350 ° C. After melting, the glass epoxy substrate was washed with water. Subsequently, the cleaned glass epoxy substrate was observed with an optical microscope.

The detergency of the flux residue was evaluated based on the criteria shown below.
○ (Good): When the flux residue is almost removed, and the surface of the glass epoxy substrate is sufficiently glossy or slightly hazy × (bad): When a small amount or a large amount of flux residue is present

  Tables 1 to 3 show the composition ratio of the flux for core solder used in each example and comparative example, and also show the evaluation results of the solidifying property and the cleaning property of the flux residue when each flux is used. There is. In addition, the numerical value of the amine for salt formation in each Table 1-Table 3, and the organic acid for salt formation is a mass part in, when the amine for salt formation is 100 mass parts. Salt consisting of amine for salt formation and organic acid for salt formation, amine not for salt formation, organic acid not for salt formation, amine halogen salt, surfactant, rosin, the total flux was 100% by mass It is mass% in a case. Moreover, comprehensive evaluation about the coagulation | solidification property of a flux, and water washability was made into evaluation of "x" which shows nonconformity as a flux, when there exists determination of x in any. Furthermore, in Tables 1 to 3, the amine for salt formation is denoted as amine A, the organic acid for salt formation is denoted as organic acid A, the amine not for salt formation is simply denoted as amine, and for salt formation Not an organic acid is simply described as an organic acid.

  As shown in Examples 1 to 7 of Table 1, in the flux composition, 10.3 parts by mass or more of tartaric acid which is an organic acid with respect to 100 parts by mass of tetrakis (2-hydroxypropyl) ethylenediamine which is an amine for salt formation. It was found that when added at 616.5 parts by mass or less, the solidification property of the flux at room temperature was a solid or a liquid of high viscosity. In addition, in Example 1, compared with the other Examples 2-7, since content of organic acid was added small, it became a result which a flux shows not a solid but a highly viscous liquid. Moreover, in Examples 1-7, it turned out that all can remove a flux residue by water also about water washability. From these results, the comprehensive evaluation of the flux of Examples 1 to 7 was “o”.

  Further, as shown in Example 8 of Table 1, in the flux composition, 102.6 parts by mass of malic acid as an organic acid with respect to 100 parts by mass of tetrakis (2-hydroxypropyl) ethylenediamine as an amine for salt formation Even when added, it was found that the solidifying property of the flux at room temperature was solid. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 8 was “o”.

  Further, as shown in Example 9 of Table 1, in the flux composition, 102.6 parts by mass of diglycolic acid which is an organic acid with respect to 100 parts by mass of tetrakis (2-hydroxypropyl) ethylenediamine which is an amine for salt formation. It was found that the solidifying property of the flux at room temperature was solid even when added in part. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 9 was “o”.

  In addition, as shown in Example 10 of Table 1, in the flux composition, 100 parts by mass of tetrakis (2-hydroxypropyl) ethylenediamine which is an amine for forming a salt, and 71. malonic acid which is an organic acid for forming a salt. Even when 2 parts by mass was added, it was found that the solidification property of the flux at room temperature was a liquid with high viscosity. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 10 was “o”.

  Further, as shown in Example 11 of Table 1, in the flux composition, based on 100 parts by mass of tetrakis (2-hydroxypropyl) ethylenediamine which is a salt forming amine, succinic acid which is a salt forming organic acid is 80. When 7 parts by mass was added, it was found that the solidification property of the flux at room temperature was a liquid with high viscosity. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 11 was “o”.

  Further, as shown in Example 12 of Table 1, 90. parts of glutaric acid which is an organic acid for salt formation in 100 parts by mass of tetrakis (2-hydroxypropyl) ethylenediamine which is an amine for salt formation in the flux composition. Even when 3 parts by mass was added, it was found that the solidification property of the flux at room temperature was a liquid with high viscosity. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 12 was “o”.

  In addition, as shown in Example 13 of Table 1, in the flux composition, citric acid as the salt forming organic acid is 87. with respect to 100 parts by mass of tetrakis (2-hydroxypropyl) ethylenediamine as the salt forming amine. Even when 6 parts by mass was added, it was found that the solidifying property of the flux at room temperature was solid. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 13 was “o”.

  Further, as shown in Example 14 of Table 2, 17.1 parts by mass of tartaric acid, which is an organic acid for salt formation, was added to 100 parts by mass of polyoxypropylene ethylenediamine, which is an amine for salt formation, in the flux composition. Even in the case, it was found that the solidifying property of the flux at room temperature was solid. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 14 was “o”.

  Further, as shown in Example 15 of Table 2, in the flux composition, 615.6 parts by mass of tartaric acid which is an organic acid for salt formation was added to 100 parts by mass of polyoxypropylene ethylenediamine which is an amine for salt formation. Even in the case, it was found that the solidifying property of the flux at room temperature was solid. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 15 was “o”.

  In addition, as shown in Example 16 of Table 2, in the flux composition, 205.2 parts by mass of tartaric acid which is an organic acid for salt formation with respect to 100 parts by mass of polyoxyethylene polyoxypropylene ethylenediamine which is an amine for salt formation. It was found that the solidifying property of the flux at room temperature was solid even when added in part. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 16 was “o”.

  In addition, as shown in Example 17 of Table 2, in the flux composition, tartaric acid which is an organic acid for salt formation with respect to 100 parts by mass of 2,2 '-(cyclohexylimino) bisethanol which is an amine for salt formation. Even when 80.2 parts by mass was added, it was found that the solidification property of the flux at room temperature was a liquid with high viscosity. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 17 was “o”.

  In addition, as shown in Example 18 of Table 2, in the flux composition, tartaric acid which is an organic acid for salt formation with respect to 100 parts by mass of 2,2 ′-(cyclohexylimino) bisethanol which is an amine for salt formation. Even when 160.4 parts by mass was added, it was found that the solidification property of the flux at room temperature was a liquid with high viscosity. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 18 was “o”.

  In addition, as shown in Example 19 of Table 2, in the flux composition, tartaric acid which is an organic acid for salt formation with respect to 100 parts by mass of 2,2 ′-(cyclohexylimino) bisethanol which is an amine for salt formation. Even when 641.5 parts by mass was added, it was found that the solidification property of the flux at room temperature was a liquid with high viscosity. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 19 was “o”.

  In Example 20 of Table 2, the total amount of flux is 100% by mass, and tartaric acid, which is a salt-forming organic acid, relative to 100 parts by mass of tetrakis (2-hydroxypropyl) ethylenediamine, which is a salt-forming amine, is 51. 90% by weight of 3 parts by weight was added, and 10% by weight of terminal amine PEG-PPG copolymer (terminal amine (polyoxyethylene glycol-polyoxypropylene glycol) copolymer) was added. Even in this case, it was found that the solidifying property of the flux at room temperature was solid. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 20 was “o”.

  Moreover, in Example 21 of Table 2, the whole flux is 100 mass%, and tartaric acid which is an organic acid for salt formation with respect to 100 mass parts of tetrakis (2-hydroxypropyl) ethylenediamine which is amine for salt formation is 51. 95 mass% of what was added 3 mass parts and 5 mass% of cyclohexylamine tetrafluoroborate were added. Even in this case, it was found that the solidifying property of the flux at room temperature was solid. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 21 was “o”.

  In Example 22 of Table 2, the total amount of flux is 100% by mass, and 100 parts by mass of tetrakis (2-hydroxypropyl) ethylenediamine as an amine for salt formation is 51. 95 mass% of what was added 3 mass parts and 5 mass% of cyclohexylamine hydrochloride were added. Even in this case, it was found that the solidifying property of the flux at room temperature was solid. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 22 was “o”.

  In Example 23 in Table 2, the total amount of flux is 100% by mass, and tetrakis (2-hydroxypropyl) ethylenediamine as an amine for salt formation is 100 parts by mass, and tartaric acid as an organic acid for salt formation is 51. 95 mass% of what added 3 mass parts and 5 mass% of ethylamine hydrobromide were added. Even in this case, it was found that the solidifying property of the flux at room temperature was solid. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 23 was “o”.

  In Example 24 in Table 2, the total amount of the flux is 100% by mass, and 100 parts by mass of tetrakis (2-hydroxypropyl) ethylenediamine which is an amine for salt formation is 51. 95 mass% of what was added 3 mass parts and 5 mass% of 2-phenylimidazole hydrobromide were added. Even in this case, it was found that the solidifying property of the flux at room temperature was solid. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 24 was “o”.

  In Example 25 of Table 2, the total amount of the flux is 100% by mass, and 100 parts by mass of tetrakis (2-hydroxypropyl) ethylenediamine which is an amine for salt formation is 51. 90 mass% of what added 3 mass parts and 10 mass% of glycerol were added. Even in this case, it was found that the solidification property of the flux at room temperature was a liquid with high viscosity. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 25 was “o”.

  In Example 26 of Table 2, the total amount of the flux is 100% by mass, and 100 parts by mass of tetrakis (2-hydroxypropyl) ethylenediamine which is an amine for salt formation is 51. 97 mass% of what added 3 mass parts and 3 mass% of lauryl dimethylamine oxide were added. Even in this case, it was found that the solidifying property of the flux at room temperature was solid. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 26 was “o”.

  In Example 27 of Table 2, the total amount of the flux is 100% by mass, and 100 parts by mass of tetrakis (2-hydroxypropyl) ethylenediamine which is an amine for salt formation is 51. 90 mass% of what added 3 mass parts and 10 mass% of 2, 2-bis hydroxymethyl propionic acids which are not the organic acids for salt formation were added. Even in this case, it was found that the solidification property of the flux at room temperature was a liquid with high viscosity. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 27 was “o”.

  In Example 28 of Table 2, the total amount of flux is 100% by mass, and 100 parts by mass of tetrakis (2-hydroxypropyl) ethylenediamine as an amine for salt formation is 51. 65 mass% of what added 3 mass parts, 10 mass% of glycerol, 10 mass% of 2, 2-bis hydroxymethyl propionic acid, and 15 mass% of ethylamine hydrobromide were added. Even in this case, it was found that the solidification property of the flux at room temperature was a liquid with high viscosity. Moreover, it turned out that water can remove a flux residue also about water washability. From these results, the comprehensive evaluation of the flux of Example 28 was “o”.

  On the other hand, as shown in Comparative Example 1 of Table 3, in the flux composition, 100 parts by mass of tetrakis (2-hydroxypropyl) ethylenediamine as an amine for salt formation and tartaric acid as an organic acid for salt formation is 5 When 1 part by mass was used, it was found that the solidification property of the flux at room temperature was low viscosity (liquid). On the other hand, it was found that water can remove the flux residue with respect to water washability. From these results, the comprehensive evaluation of the flux of Comparative Example 1 was “x”.

  In addition, as shown in Comparative Example 2 of Table 3, in the flux composition, 100 parts by mass of tetrakis (2-hydroxypropyl) ethylenediamine which is an amine for forming a salt, and 99. adipic acid which is an organic acid for forming a salt. In the case of 9 parts by mass, it was found that the solidification property of the flux at room temperature was a liquid of high viscosity. On the other hand, it was found that the water residue could not be completely removed by water with respect to water cleaning properties. From these results, the comprehensive evaluation of the flux of Comparative Example 2 was “x”.

  Further, as shown in Comparative Example 3 of Table 3, the total amount of the flux is 100% by mass, and tartaric acid which is an organic acid for salt formation with respect to 100 parts by mass of tetrakis (2-hydroxypropyl) ethylenediamine which is an amine for salt formation. Was added to form 80% by mass of a salt, and 20% by mass of acid-modified rosin, which is a rosin, was added. In this case, it was found that the solidifying property of the flux at room temperature was solid. On the other hand, it was found that the water residue could not be completely removed by water with respect to water cleaning properties. From these results, the comprehensive evaluation of the flux of Comparative Example 3 was “x”.

  In the above-described embodiment, an example in which each of malonic acid, succinic acid, glutaric acid, glutaric acid, tartaric acid, malic acid, diglycolic acid and citric acid is used alone as the salt-forming organic acid has been described. Even when using at least two or more of malonic acid, succinic acid, glutaric acid, glutaric acid, tartaric acid, malic acid, diglycolic acid and citric acid as organic acids for use, the solidifying property of the flux is solid or high viscosity liquid It turned out that it became. It was also found that the flux residue can be washed with water also with respect to water washability.

  Moreover, it can be used also as a flux for solder pellet coating by heat-melting the flux mentioned above and apply | coating to the surface of a solder pellet. The flux residue after soldering using flux-coated pellets was similarly water-washable.

DESCRIPTION OF SYMBOLS 10 core solder 20 solder 30 flux 40 solder pellet main body 50 flux coat pellet

(1) The flux according to the present invention contains an amine for salt formation and an organic acid for salt formation, and the amount of the organic acid is 10 parts by mass or more and 645 parts by mass or less with respect to 100 parts by mass of the amine. rosin is Ri free der, solid at 25 ° C. or, rotational viscosity was rotated at 6Hz plates rheometer at 25 ° C. is characterized by comprising the liquid is 3500Pa · s or more.

( 8 ) The core solder according to the present invention is characterized by including linear solder and the flux according to any one of the above (1) to ( 7 ) filled in the solder. I assume.

( 9 ) The flux coated pellet according to the present invention is characterized in that the solder pellet is coated with the flux described in any one of the above (1) to ( 7 ).

Claims (10)

An amine for salt formation and an organic acid for salt formation;
10 parts by mass or more and 645 parts by mass or less of the organic acid with respect to 100 parts by mass of the amine,
A flux characterized by being free from rosin. The flux according to claim 1, wherein the amine contains at least one or more of polyoxyalkylene ethylenediamine and 2,2 '-(cyclohexylimino) bisethanol. The flux according to claim 1 or 2, wherein the organic acid comprises at least one or more of malonic acid, succinic acid, glutaric acid, tartaric acid, malic acid, diglycolic acid and citric acid. When a flux containing a salt formed by the amine for salt formation and the organic acid for salt formation is 100% by mass,
The flux according to any one of claims 1 to 3, comprising 0 mass% or more and 10 mass% or less of an organic acid which is not for salt formation. When a flux containing a salt formed by the amine for salt formation and the organic acid for salt formation is 100% by mass,
The flux according to any one of claims 1 to 3, which contains 0% by mass or more and 10% by mass or less of an amine not for salt formation. When a flux containing a salt formed by the amine for salt formation and the organic acid for salt formation is 100% by mass,
The flux according to any one of claims 1 to 3, comprising 0% by mass or more and 15% by mass or less of an amine halogen salt. When a flux containing a salt formed by the amine for salt formation and the organic acid for salt formation is 100% by mass,
The flux according to any one of claims 1 to 6, comprising 0 mass% or more and 10 mass% or less of a surfactant. The liquid according to any one of claims 1 to 7, characterized in that it is solid at 25 ° C or a liquid having a rotational viscosity of 3,500 Pa · s or more obtained by rotating the plate of the rheometer at 6 Hz at 25 ° C. flux. With linear solder,
The flux according to any one of claims 1 to 8, filled in the solder.
It is characterized in that it contains solder. A flux coated pellet characterized in that the solder pellet is coated with the flux according to any one of claims 1 to 8.

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